1. Field of the Invention
The present invention relates to a thermal spray coating, a member for semiconductor manufacturing equipment, a feedstock material for thermal spray, and a method for producing a thermal spray coating.
2. Description of the Related Art
In semiconductor manufacturing equipment used for dry processes, plasma coating, and the like in semiconductor manufacturing, a halogen-based plasma, such as F or Cl, having high reactivity and corrosiveness is used for etching and cleaning. Members assembled into such semiconductor manufacturing equipment are required to have high corrosion resistance. In materials for such members, long-term use causes corrosion to progress gradually, and occurrence of dust and the like results in contamination of semiconductors. Thus, high corrosion resistance is needed. Alumina, aluminum nitride, yttria, and the like are known as materials having high corrosion resistance, and have been used in semiconductor manufacturing equipment. As a material having higher corrosion resistance than such materials, the present inventors have developed a ceramic material containing mainly magnesium, aluminum, oxygen, and nitrogen and having, as a main phase, a crystal phase of a MgO—AlN solid solution in which aluminum nitride is dissolved with magnesium oxide (PTL 1). This material has very high corrosion resistance and a smaller water-absorbing capacity than magnesium oxide, and exhibits high denseness and a good insulating property as a bulk. Therefore, it is believed that the ceramic material is very suitably used for members, such as heaters and electrostatic chucks, in semiconductor manufacturing equipment.